We have an issue whereby not-nullable fields in our Oracle database do not exist in our TimesTen database. So the GUI part of our application writes to Oracle and then our application engine reads from TimesTen.
The problem is that some fields are not-nullable in Oracle and therefore we need them in our mapping files.
However, when we read the corresponding object from TimesTen we get an error saying that the column does not exist.
We cannot add these columns to TimesTen as they are not used by our application engine and performance/memory usage is key.
I’ve tried making these properties in question to be “lazy” in the mapping files but this didn’t seem to work.
We cannot specify default values either in Oracle for these not-nullable fields, so this seems to be tricky to resolve!
What other options do we have from a Hibernate point of view?
Thanks
As far as I know Hibernate always makes sure all columns which are mentioned in the mapping file exist in the database, too. So you can’t do it in one mapping file.
Use two mapping files. And then you also use two hibernate.cfg.xml, one for the GUI part, one for the application engine. The difference in these two configuration files is, they refer in their mapping properties to the different mapping files. When you give the names of these configuration files as a parameter to the configure() method in the GUI part and in the application engine, then the rest of the Java code can be exactly the same for your two applications.
If the two different mapping files (for Oracle & TimesTen) for one table should contain a lot of same xml code and you don’t want to have this xml code twice in your files, then you can use the xml mechanism of including files (with
[<!ENTITY namexxx SYSTEM "filename">]and&namexxx).